Turbine blading



A. T. KASLEY TURBINE BLADING Filed March 28. 1924 Nov. 24, 1925- z sheets-sheet 1 r1. 7Ih'as/ey INVENTOR ATTORNEY Nov. 24, 1925- 1,562,970

A. T. KASLEY TURBINE BLADING Filed March 28, 1924 2 Sheets-Sheet 2' WITNESSES:

ATTORNEY ,4; rlraa/ey INVENTOR Patented Nov. 24, 1925.

UNITED STATES ALEXANDER T. KASLEY, F MOORE, PENNSYLVANIA, ASSIGNQR TO VVESTINGHO'USE PATENT FFIQE.

TURBINE BLADING.

Application filed March 28, 1924. Serial No. 702,489.

To all whom it may concern:

Be it known that I, ALEXANDER 'l. KAsLnY, a citizen of the United States, and a resident of Moore, in the county of Delaware and State of Pennsylvania, have invented a new and useful Improvement in Turbine Blading, of which the following is a specification.

My invention relates to blade fastening means for turbines and it has for its object to provide apparatus of the character designated which may be simply, easily and inexpensively manufactured and installed, and which shall be highly efiective in operation to retain turbine blades in place over longperiods of service.

In the accompanying drawing, Fig. 1 is a side view in section of a turbine of the single-disc impulse type, being typical of the general type of apparatus in which my invention may be employed; Fig. 2 is a side view of a turbine disc provided with a supplemental ring as employed in the manufacture of my device; Fig. 3 is a perspective view of a blade adapted to be employed in the disc of Fig.2; Fig. 4: is a view of the disc of Fig. 2 containing blades of the type shown in Fig. 3; Fig. 5 is a top view of the blading shown in Fig. 4 prior to the forma tion of a ring holding boss; Fig. 6 is a similar view after the provision of a boss and the application of suitable retaining rings; Fig. 7 is a sectional view of the turbine disc, together with a blade in side elevation; Fig. 8 is a side view of the completed structure; Fig. 9 is a view similar to Fig. 7 and embodying a modification in the ring mounting; Fig. 10 illustrates a modification of my invention wherein blades are retained in place by a pin rather than by an enlarged root; Fig. 11 illustrates one method of applying my invention to a disc carrying two rows of blading; and Fig. 12 illustrates another method of forming the same general structure as shown in Fig. 11.

In the manufacture of turbines, particularly of the disc type, ithas been proposed to hold the blades in place either by transverse pins projecting through root portions thereof, or by employing expanded root portions engaging in undercut notches. While these structures are adequate so long as the holding means remains in place, they at times fail because of slippage of the retaining means out of its appropriate position.

Accordingly, I mount blades in suitable blade-carrying elements in either one of the aforementioned ways, and I then shrink retaining rings on one or both sides of the blade-carrying means whereby such escape of blade fastening structures is prevented. Preferably these retaining rings are shrunk in place upon bosses which taper slightly toward the disc so that, in shrinking, the rings are twisted or dished into firm engage ment with the blades or blade roots to form a very tight fastening device.

Referring to the drawing for a more de tailed understanding of my invention, I show a turbine of the. single impulse wheel type in Fig. 1 embodying a casing 15, a shaft 16, a disc 17 and a nozzle 18, any of which elements maybe widely modified;

without departing from the spirit and scope of my invention.

In the manufacture of the disc 17, as

shown in Fig. 2, it is provided with a temporary encircling ring 20 which is preferably shrunk in place. Holes 21 are then drilled, largely within the body of the disc 17, but partially within the ring 20. The ring 20 is then removed, leaving a plurality of transverse peripheral notches in the disc 17, these notches being of circular cross section. Suitable blades for mounting in the disc 17 are provided as shown in Fig. 3, each blade 22 being provided with a transverse root portion 23 of substantially cylindrical cross section except that I preferably leave a fiat portion on the under side thereof, as indicated at 24.

The blades 2222 are slipped within the notches 21-21, as shown in Fig. 4, the flat portions 24: on the bottoms of the roots 23 causing the formation of segmental openings at the bottoms of the notches 2l21. I then place suitable segmental-shaped wedges in each of these openings, as indicated more clearly at 25 in Fig. 7; the effect of the wedge being to cause firm engagement of the respective root portions in their appropriate holding. notches.

The resultant structure to this point is shown in plan view in Fig. 5, the blades 22-22 extending substantially to the outer surface of the disc 17 and the root portions 23-23 protruding through the sides of the disc, as indicated. I then machine away the ends of the root portions 23, together with a portion of the disc l7, so as to form circumferential shoulders for the reception of retaining rings 26-26, as clearly shown in Fig. 7, the plan view of the structure. thus. formed being shown in Fig. 6, and the side view of. the finished rotor being; shownin Fig. 8.

The rings 26. are shrunk firmly in place.

and effectually prevent the escapeof the root Referring-to Fig. 9, I showiin enaggerated;

form a feature of my invention which I con: sider highly advantageous; The shoulders or bosses formed on the. disc 17. for the. re-. ception of the retaining. rings 26-26 may run normal to the plane of thedisc, but these holding bosses preferably taper slightly to.- ward the disc, whereby when. the rings 26 26 are shrunlrin-place, the shrinking upon said tapered bosses causes the rings to slightly twist or dish, whereby they are.

forced into firm engagement, both with the roots of the bladesand with the. blade hold ing means, asind-icated; Furthermore, the rings are more effectually. held in place than wouldbe the case. ifthey were shrunk upon a cylindrical boss.

In the term of. myv invention shown in, lfig. 10, the disc 17 is provided with a pair of pe-. ripheral flanges 30 and 31 between whichv a suitably formed root portion 32: isdisposed, being held inplace as bysuitable transverse holding pins 2626 are then. mounted inplace to prevent the escape of the pins 33: and also to give a smooth and pleasing appearancetothe entire structure.

In the form of'my. invention shown in- Fig.

11. a disc 17 carries a rim. ill-having two blade-carrying flanges ll and; 42, thereupon, each of which carries suitableblading as. in.- dicated, this blading. being shown, held in place in the same manner asi-ndicated in Fig. 7. This structure has the marked disadvantage that the inner rings 26 ..26 cannot be formed integrally and slipped: into place, but they must be split in one or more places,

Suitable retaining. rings,

placed betwen the flanges il and 42 and then welded or otherwise joined into continuous rings, all prior to the shrinkage operation. Inasmuch as this isa troublesome and unsatisfactory operation, I prefer to employ the structure shown in F ig. 12 for a disc carrying two rows of blad-ing. The disc 17" has a rim 4:0 with blade holdingnotches drilled in from opposite sides thereof for the reception ofblade holding roots, all of the general typeshown in Fig. l, Suitable rings 26-26 are then disposed in place to prevent the es cape of the blades, movement of the blade holding structures toward the center of the disc 17" being prevented. by, the. solid abutments indicated at 45 45 \Vhile I have shown my invention in several forms, it will be obvious to those skilled ingthe art; thatit is notwso limited, but is susceptible of various other changes and modifications, without departing rom the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth inthe. appended it claims.

What I claim is.

1. In an elastic fluidturbine, the, combination with a blade-carrying disc, of blades carried thereby and mounted by holding means extending, transversely of said disc and holding rings. to. prevent movement of said holding. means. transversely of. said disc, saidholding rings being-shrunk in place.

2. In an elastic fluid turbine, the combination with a blade-carrying disc, of an inwardly tapering boss formed around the disc near its periphery, blades carried by the disc-and mounted by holding means extendingtransversely of said disc, and a holding ring to, prevent; movement of said holding meanstransuersely of said. disc, said holding ring being slipped over the boss and; shrunk in. place-thereon, whereby said ring is. twisted into. firm engagement with said. holding means.

3. In an elastic fluid, turbine, the curablnation with a. disc provided with a plurality of transverse undercut notches in the periphery thereof, of; bladesprovided with root portions. adapted to fit within said notches, respectively, bosses formed on the sides of the disc neanthe periphery thereof and retaining rings mounted upon the sides oi said disc and shrunk upon the bosses to restrain said root portionsdn place.

4:. In an. elastic fluid. turbine, the combination witha disc provided with a plurality of trans qerse.undercut notches. in the periph eny thereof, of blades, provided with root portions adapted to fit within said. notches, respectively, bosses formed on the sides of the. disc adjacent the notches and tapering slightly inward of the disc, and retaining rings mounted upon the sides of lil said disc and shrunk upon the bosses to re strain said root portions in place, whereby said rings in shrinking are twisted into firm engagement with saidblades.

5. In an elastic fluid turbine, the combination with a disc provided with a plurality of transverse undercut notches in the periphery thereof, of blades provided with root portions adapted to fit within said notches and to substantially fill the same except for an opening at the bottom of each notch, a tightening wedge in each of said openings, respectively, and retaining rings mounted upon the sides of said disc to restrain said root portions and said wedges 1n place.

(3. In an elastic fluid tiiirbine, the combination with a disc provided with a plurality of transverse undercut notches in the pe riphery thereof, of blades provided with root portions adapted to fit within said notches and to substantially fill the same except for an opening at the bottom of each notch, a tightening wedge in each of said openings, respectively, bosses formed on the sides of the disc adjacent the notches, and retaining rings mounted upon the sides of said disc to restrain said root portions and said wedges in place.

7. In an elastic fluid turbine, the combination with a disc provided with a plurality of transverse undercut notches in the periphery thereof, of bosses formed on the sides of the disc adjacent the notches and tapering slightly toward the disc, blades provided with root portions adapted to fit within said notches and to substantially fill the same except for an opening at the bottom of each notch, a tightening wedge in each of said openings, respectively, and retaining rings mounted upon the sides of said disc and shrunk upon the bosses to restrain said root portions and said wedges in place, whereby said rings in shrinking are twisted into firm engagement with said blades.

8. In an elastic fluid turbine, the combination with a disc provided with a trans verse undercut notch in the periphery there of, said notch being of circular cross-section, of a blade having a root portion shaped to fit within said notch except for a seg mental opening at the bottom thereof, a segmental wedge disposed within said opening and adapted to tightly fill the same and a retaining ring on one side of said disc and overlying said root portion and said wedge, whereby said elements are restrained from movement out of said notch in the direction of said ring.

9. In an elastic fluid turbine, the co1nbination with a disc provided with a transverse undercut notch in the periphery thereof, said notch being of circular cross-section, of a blade having a root portion shaped to fit within said notch except for a segmental opening at the bottom thereof, a segmental wedge disposed within said opening and adapted to tightly fill the same and a retaining ring on one side of said disc and overlying said root portion and said wedge, whereby said elements are restrained from movement out of said notch in the direction of said ring, said ring being shrunk in place upon a suitable boss provided on the side of said disc.

10. In an elastic fluid turbine, the combination with a disc provided with a trans verse undercut notch in the periphery there of, said notch being of circular cross-section, of a'boss formed on the side of the disc adjacent the notch and tapering silghtly toward the disc, a blade having a root portion shaped to fit within said notch except for a segmental opening at the bottom thereof, a segmental wedge disposed within said openand adapted to tightly fill the same and a retaining ring shrunk on the boss and overlying said root portion and said wedge, whereby said elements are restrained from movement out of said notch in the direction of said ring, and said ring in shrinking is twisted into firm engagement with said blade.

, 11. In an elastic fluid turbine, the combination with a disc provided with a plurality of transverse undercut notches in the periphery thereof, of blades provided with root portions adapted to fit within said taining ring shrunk on the boss and overlying said root portion, whereby said root portions are restrained from movement out of said notches in the direction of said ring, and said ring in shrinking is twisted into firm engagement with said blades.

13. In an elastic fluid turbine, the combination with a blade-carrying disc, of blades carried thereby and mounted by holding means extending transversely. of said disc, and a holding ring shrunk upon a boss upon one side of said disc, said ring overlying said holding means, whereby they are restrained from movement out of said disc in the direction of said ring.

1%. In an elastic fluid turbine, the comblades carried thereby and mounted by holding means extending transversely of said disc, av hoss formed on one side of the disc,

and a holding ring: shrunk upon the-b0ss,. said 1111; overlying szud holdmg means,-

and said boss tapering slightly toward, said,

disc, whereby said in shrinking is twisted into fil'mengagement with. said blades.

In testimony whereof, I have hereunto subscribed. my nmnethi-s 17th day of March, 192%.

ALEXANDER T. KASLEY; 

